Dicyanoacetylene

Dicyanoacetylene
Names
Preferred IUPAC name
But-2-ynedinitrile
Identifiers
3D model (JSmol)
ChemSpider
  • InChI=1S/C4N2/c5-3-1-2-4-6 ☒N
    Key: ZEHZNAXXOOYTJM-UHFFFAOYSA-N ☒N
  • InChI=1/C4N2/c5-3-1-2-4-6
    Key: ZEHZNAXXOOYTJM-UHFFFAOYAR
  • N#CC#CC#N
Properties
C4N2
Molar mass 76.058 g·mol−1
Density 0.907 g/cm3
Melting point 20.5 °C (68.9 °F; 293.6 K)
Boiling point 76.5 °C (169.7 °F; 349.6 K)
Thermochemistry
+500.4 kJ/mol
Related compounds
Related compounds
Carbon suboxide
Cyanogen
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Dicyanoacetylene, also called carbon subnitride or but-2-ynedinitrile (IUPAC), is a compound of carbon and nitrogen with chemical formula C4N2. It has a linear molecular structure, N≡C−C≡C−C≡N (often abbreviated as NC4N), with alternating triple and single covalent bonds. It can be viewed as acetylene with the two hydrogen atoms replaced by cyanide groups.

At room temperature, dicyanoacetylene is a clear liquid. Because of its high endothermic heat of formation, it can explode to carbon powder and nitrogen gas, and it burns in oxygen with a bright blue-white flame at a temperature of 5,260 K (4,990 °C; 9,010 °F), the hottest flame in oxygen; burned in ozone at high pressure the flame temperature exceeds 6,000 K (5,730 °C; 10,340 °F).[1]

  1. ^ Kirshenbaum, A. D.; Grosse, A. V. (1956). "The Combustion of Carbon Subnitride, C4N2, and a Chemical Method for the Production of Continuous Temperatures in the Range of 5000–6000K". Journal of the American Chemical Society. 78 (9): 2020. doi:10.1021/ja01590a075.